Electric bell.



IVI. SUWA.

ELECTRIC BELL.

APPucATloN flu-:D JULY 3, 1915.

Patented Apr. 10,1917.

mums versus cu. Punruma. wAsHms MEGHISUYE SUWA, 0F TOKYO, JAPAN.

ELECTRIC BELL.

Application filed 3111y'3, 1915.r

To all whom t may concern.'

Be it known that l, MroHisUYn SUWA, a subject of the Emperor of Japan, and a resident of the city ot rokyo, Japan, have invented new and use-ful improvements in Electric Bells, of which the following is a specication.

IThis invention relates to improvements in electric bells and it resides mainly in a novel arrangement of the armature with respect to the poles of the electro-magnet forming part of the bell.

An object of the invention is to provide an electric magnet having pole-pieces which entend approximately longitudinally with respect to the axis of the electro-magnet, in contradistinction ot known devices, wherein the pole shoes are located in transverse planes, with respect to the axis of the magnet or its core.

Another object of the invention is to provide a simple armature which consists of a straight strip otsuitable metal supported so as to have its ends in opposition to opposite pole-pieces, the support tor said armature being placed approximately midway between said poles, so that even at a slight oscillation of the armature the latter will come into contact with said poles, or will be removed therefrom.

another object of the invention is to provide an electric bell in which one of the pole shoes extending approximately in direction ot the longitudinal axis of the electro-magnet serves as a means for holding the support to which the armature is movably secured and tor locating said armature with respect to said extension, so that the central portion et the armature normally remains in contact with the extension. The residuary magnetism remaining within the extension after the energization of the electro-magnet has ceased, is suliiciently large to cause attraction of the respective end of the armature to the said pole, even it a very weak current only is sent through the winding of the electro-magnet, whereby the useful life of batteries in connection with this electric bell is lengthened. L

An object of the invention is also to provide an electric bell in which both of the poles of the electro-magnet are utilized to influence directly the armature, in contradistinction ot known bells, in which the ar1na- Spccication of Letters 'Eatent Patented Apr. im), ilQrU..

Serial No. 37,968.

ture is placed immediately in front ot one of the poles only, and is influenced therefore by thesaid pole exclusively.

llVith these and other objects in view l have illustrated several embodiments of the invention in the accompanying drawings, wherein- Figure l is a front elevation of an electric bell of this character;

Fig. 2 is a side elevation of the same;

Fig. 3 is a diagrammatic view for illustrating the electrical connections as well as the mechanical means for suspending the armature l is a trent elevation ot a electric bell of this character;

Fig. 5 is a side elevation of the modified embodiment shown in Fig. l;

Fig. is a diagrammatic view similar to Fior 3 to illustrate the modied embodiment, and

Fig. 7 is a plan detailed view of the ar mature used in connection with this bell.

rllhe bell comprises a baseboard S having terminal screws near the upper edge of the sameand a bell 9 mounted on a stud at a suitable distance from the surface et the baseboard near the lower end. An electromagnet 3, comprising a winding and a magnetizable core, is mounted on the board. Pole plates at the ends of the core extend transversely with respect to the longitudinal axis of the same, and the ends ot said plates are bent, so as to Yterm angular extensions et, located in dierent planes which are parallel to the longitudinal axis of the core.

The armature l, consisting, as shown in Fig. 7, of a strip of metal, has supporting pins 2 near the central portion, and this arn mature is held in a hoop or bailwshaped member 5 which is supported by a screw, or in some other suitable way, on the baseboard of the bell. From Figs. l and 3 it will be seen that the armature l is arranged. with respect to the angular extensions 4f of the pole shoes so that one end of the armature is located in opposition to that surface or" a polar extension l which is directed away from the electro-magnet 3, while the other end is in opposition to that polar surface l which is directed toward the electromagnet 3. lVhile the armature may oscillate freely on its pivotal points 2 within the supporting strip 5, it is obvious that this modified oscillation is limited in either direction by the contact of the armature with the polar extensions of the pole shoes.

A rod 6 fastened to one end of the armature carries at its free end the hammer 7,

which is adapted to strike the bell 9. when.

the armature is attracted by the pole shoes. This. rod G also carries intermediate its ends a platinum plate adapted to contact with the platinum point 12 of the spring 11 when the armature is in its normal position at a distance from the pole extensions il. To the opposite end of the armature 1 the enel of a spring 10 is fastened, the other end of which is attached to the opposite polar extension. The spring 11, which is insulated from they other metal parts of the device, is connected by means of the conductor 13 with the winding of the electro-magnet. The operation, therefore, is approximately as follows In its normal position the armature 1 is at a distance from both of the pole extensions. 4- and makesv contact with the point 12 of the spring 11. lWhen a circuit is closed through the bell, the current passes through the winding of the electrosmagnet into: theI conductor 13, through the spring 11, contact point 12, armature 1, spring 10, pole 41 core of the electro-magnet, and through a wire indica-ted' in connection with one of the polar extensions, back to the battery (not shown). The` energization of the electro-magnet will cause both of the poles toy attract thev respective ends: of the armature,y soy that thehammer Z strikes the bell. This attraction also causes the removal of the contact platev of the .armature from the contact point 12, vandV the interruption of the current. The armature, therefore, will be returned to its normal position by the spring 10, whereby the current is closed again at the contact point 12. The armature is again attracted and so on' until the current through the winding'- of the electromagnet 3 is interrupted.

While in the embodiment described the angular extensions-1iL of the pole shoes have about the same length, it w'll be noted with respect to the embodiment illustrated in Figs.. a to.L 6l that one polar extension a is made considerably longer than the pol-ar extension 42 projecting from the other pole shoe of the magnetic core. The end of the extension 41: isv always kept in Contact with a surface point of the armature, even though the armature may oscillate away from the other end or operative portion of the same angular extension. The result of this arrangement will be that not only large surfaces of pole shoe and armature are brought into contact with each other, but also that on account of the permanent contact of the end of the angular extension with a point located between the poles of the armature, a slight pull exerted by the angular'extension a" on the armature will be suflicient to cause oscillation of the armature. This means that even weakened batteries which, under normal' conditions, would have indicated a state of exhaustion beyond use-fulness may be utilized for the operation. of the bell.

l claim: Y

1. In an electric bell, an electro-magnet, a core, pole shoes on saidV core, saidl pole shoes being provided with. angular extensions locatedy in planes parallel to the of the core, and an armature oscillatori-ly mounted intermediate its ends, the endsof sai-d armature being adapted toy engage with opposite sides sai-d angular: polar extensions.

2. ln an el'ectricbell, the combination with ain electro-mao'net of a. core, polar projections on said core bent direction towardl each other and located in planes parallel to the longitudinal axis of the core, one of said polar projections being longer.'` than the other polar projection, and an armature.- oscillaftably mountedv between said polar projections, opposite ends' of said armature being each in opposition to onek of said. polar' projections, the. center portion of said armature being in constant contact with the Y said longer polar projection.

3. In an electric bell, the combination of an electro-magnet, a core, polar projections on the core, bent portions on they pol-ar pros jections extending toward each other in different planes parallel to the longitudinal axis of' the core, and an armature comprising a straight strip of metal having supporting pinsnear its. center portion, the ends of the armaturev to engage with opposite sides of the bent portions, onev of said bent porti-ons being in continuous contact with they center Vportion of the armature;

In witness whereof I have signed this specification in presen-ce of two Witnesses.

MICHISUYE SUWA.

Witnesses:

DEN KIDO, Eier-rino- Copies of this patent may he obtained for ve cents each, by addressingl the Commissioner of Patents, Washington, D. C. 

